Roofing



Patented June 19, 1934 UNITED STATES PATENT OFFICE ROOFING No Drawing. Application May 28, 1930, Serial N 0. 456,801

18 Claims.

My invention relates to coating or sizing, and, in the case of porous materials, impregnating to some extent, grit or granules intended for imposition upon composition or prepared roofing.

By composition or prepared roofing I mean that type of roofing which consists of a layer of rag, paper, asbestos, or other fibrous material saturated with or impregnated by a relatively low melting point bituminous or hydrocarbon material and upon which is superimposed a layer of higher melting point bituminous or hydrocarbon compound into which is embedded grit; granules such as crushed slate, gravel, stone, or analogous material.

In the manufacture, storage, and use of this type of roofing it frequently happens that cer-- tain faults and objectional defects develop which detracts from its appearance, marketability and life. One of these defects consists of the dis'coloration of the surfacing mineral granules by certain oils of the bituminous or hydrocarbon ma terials which in time stain or tint the mineral granular surfacing of the roofing thereby chang ing the original color of the surfacing material so that roofing stored for various periods of time is of different color or shade than it was originally. As a result of this discoloration, roofing of various ages when applied to the same roof is easily discernible. This detracts from the appearance of the roof and frequently causes complaints to the manufacturer.

Another defect to which this type of roofing is susceptible is the physical action known as blistering". One of the contributory causes of this action is the presence of moisture which has been absorbed by the granular surfacing and which upon relatively rapid temperature rise expands into the coating material thereby creating a cavity. A cavity thus formed may. and 40 frequently does, break open leaving the saturated or impregnated base covered by only a thin film of coating exposed to the weather. This action is very detrimental to both the life and appearance of the roofing and is often the cause of com- 45 plaints.

Still another defect of this type of roofing is its tendency to become discolored in use by the action of the elements in causing foreign matter to penetrate or adhere to the surfacing granules,

50 thereby destroying their original color and ap pearance.

One of the objects of my invention is to overcome, and my invention in fact overcomes, each and all of the above mentioned defects because 55 by the practice thereof the entire surface of each granule is so treated before application to the roofing that it is completely coated, and when porous, its pores are filled with a substance which under storage and exposure conditions is water insoluble and bituminous oil insoluble, transparent or semi-transparent and which preserves the natural, original color and appearance of the granule and consequently preserves the original color of the roof. A continuous film is thus formed about each grit particle so that it is adequately sealed against the deleterious action of oil, water and other foreign materials under normal storage and exposure conditions.

Another object of the invention is to enable composition roofing material to be packed closely together without danger of discoloration in or on the grit surface.

A further object of the invention is to completely encase each mineral granule on roofing of the type described, in a protective film, without altering the original color of the grit surfacing material.

A further object is to provide a roofing surfacing material for composition roofing having a pleasing appearance and possessing lasting qualities, in an easy and economical manner.

The transparent or semi-transparent substance is applied in liquid form to the mineral grit or granules prior to their application in the retaining base material. Application of the liquid is effected by means of a mixing agitator, trommel or revolving mixer or any mixing device suitable for securing a thorough and intimate mix of the liquid with the grit or granules. The grit or granules so treated are subsequently dried either by natural or artificial means to evaporate or vaporize the vehicle of the liquid medium, leaving a hard or semi-hard, transparent or semitransparent film on each grit particle or granule. Grit so treated is similar in color and appearance to untreated grit of the same quality: in fact the original color of the granular material is permanently preserved.

I have found that a solution of natural or syn thetic resin or a mixture of both in an organic solvent. such as Kauri gum or Amberol dissolved in naphtha or benzol, is satisfactory for use with this invention. but the invention is not limited to the use of this specific type of material. Other materials can be used to secure a transparent or serni-transparent coating or impregnation of the granules. Among such materials are water insoluble caseinates; water soluble caseins so treated to form insoluble condensates when dried; resinous, oleo-resinous and pyroxylin types of spirit varnishes or lacquers; and other cellulose base materials. I do not confine myself to the materials listed above but broadly use any material which can be conveyed in liquid form to the granules to produce a film suitable for my purpose which is substantially water and bituminous oil insoluble; oil stain-resistant, and transparent or semi-transparent.

The amount of liquid used to produce the transparent or semi-transparent film varies depending upon the nature of the liquid and film material used and upon the porosity or absorption capacity of the grit or granules treated. When using the solution of a resin and an organic solvent above referred to the amount of liquid used is approximately two gallons per ton to ten gallons per ton of grit or granules treated, when green stone is used as a surfacing material.

I am aware that certain processes exist for the treating of grit or granular surfacing materials with fluids carrying coloring agents, whereby the color of the grit is artificially created. The invention herein however is not aimed at artificially coloring granular material but seeks to provide for the retention of the natural color and appearance of the grit and to obtain complete protection of the grit from the action of oil, water and other foreign agents.

I am aware also that certain processes exist for the spraying or brushing of various materials over the surface of applied grit in order to prevent staining and discoloration. My invention is a distinct improvement over such treatment as the granular material used in the manufacture of prepared roofing is completely encased in a ma terial which is substantially insoluble in water and in the commonly used asphaltic or hydrocarbon oils. With my invention no cracking in the surface film of protective material is possible and staining cannot take place from oils in the under side of the grit which, in known constructions of this type, are directly exposed to the action of such oils. In other words the granules when treated in accordance with the principles herein stated, are completely encased, before they are embedded in the coating of the prepared base, in a film which is substantially oil and water insoluble. Thus all faces and surfaces of the grit are protected so that no staining or discoloration can occur from the top or from the under surface which is embedded in the coating. Roofing so manufactured can be rolled and bent during handling without cracking or rupturing the protective film on the granules and thus the granules cannot be stained or disfigured by reasons of the formation of cracks which might allow foreign materials to act directly on the grit. Moreover, roofing of the type herein described can be stacked or rolled so that the surface of the grit is in contact with the under surface of adjacent elements or adjacent parts of the rolled sheet, without danger of discoloration from oil.

I am also aware that it has been suggested to oil green stone granular surfacing for prepared roofing material in order to secure a more desirable green color for prepared roofing. The invention herein does not include oiling of the grit or granules and differs from oiling of grit (1) in that it does not change the color of the natural granular material in any way, and (2) it covers the grit particles with an insoluble film, not a soluble oil.

My improved roofing material, when manufactured in accordance with the principles here in laid down is not affected by moisture or by any oily material. Each g'ranuleis completely protected against action by water or by any oil which is present in the roofing base. The entire grit surface therefore is protected from the action of water so that no blistering in the roofing material can take place and staining from asphaltic or hydrocarbon oils is completely eliminated.

Having thus described my invention I claim:

1. The process of treating granular material intended for imposition on composition roofing which comprises completely encasing each granule of the material in an unvitrifiable substantially transparent coating which is substantially without color and which is substantially water and oil insoluble.

2. The process of manufacturing prepared roofing surfaced with granular surfacing material which includes the step of covering the granular surfacing material, before embedding same in the composition base of the roofing, with a film of unvitrifiable and substantially transparent material which is substantially without color and which is substantially insoluble in water and the bituminous oils of the prepared roofing.

3. The process of manufacturing roofing material surfaced with granular surfacing material which includes the step of encasing each particle of granular surfacing material in a substantially colorless and transparent film of unvitrifiable coating material deposited from solution in a suitable vehicle, said film being substantially insoluble in water and in the asphaltic or hydrocarbon oils present in the base of composition or prepared roofings.

4. The process of treating granular material for surfacing composition roofing, which comprises covering the granules by deposition from a suitable solvent with an unvitrifiable transparent coating which is substantially without color and which is insoluble in water and is substantially insoluble in the oils of the bituminous compounds present in the roofing.

5. The process of manufacturing composition roofing surfaced with granular surfacing material, which comprises treating the granules of the granular surfacing material with a solution in a suitable solvent of a material which when deposited from solution and dried upon the granules is unvitrifiable and transparent and substantially without color and is insoluble in water and substantially insoluble in the oils of the bituminous coating of the composition roofing, drying the granules, and embedding the granules in the bituminous coating as surfacing material.

6. The process of manufacturing composition roofing material surfaced with granular material which includes the step of treating the granular surfacing material with an uncolored transparent solution of a resinous gum.

7. The process of treating granular mineral material, which comprises applying to the granules a substantially colorless and transparent coating of a resin.

8. The process of treating granular mineral material, which comprises applying to the granules an uncolored transparent coating of a resin deposited from a solution of the resin in a suitable solvent.

9. The process of treating granular mineral material. which comprises applying to the granules an uncolored transparent solution of a natural resin in an organic solvent.

10. The process of treating granular mineral material, which comprises applying to the granules an uncolored transparent solution of a synthetic resin in an organic solvent.

11. The process of treating granular material for surfacing the bituminous coating of roofing, which comprises treating the granules with an uncolored transparent solution of Kauri gum in naphtha.

12. The process of treating granular mineral material, which comprises applying to the granules an uncolorecl transparent oleo-resinous varnish.

13. The process of treating granular mineral material, which comprises applying to the granules an uncolored transparent resinous lacquer.

14. The process of treating granular mineral material, which comprises applying to the granules an uncolored transparent pyroxylin lacquer,

15. A product of manufacture, comprising granular mineral material and a transparent substantially colorless coating thereon of an unvitrifiable material which is insoluble in water and substantially insoluble in bituminous oils.

16. A product of manufacture, comprising granular mineral material and a transparent film of an uncolorecl resin on the surface of the granules.

17. Granular mineral material having thereon an uncolored transparent encasing film of a resinous gum.

18. Composition roofing surfaced with granular mineral material having on the granules an uncolored transparent coating of a resinous gum.

ARTHUR DAWES MACNU'I'I.

CERTIFICATE OF CORRECTION.

Patent No. 1,963, 752.

June l), I934.

ARTHUR DAWES MacNUTT.

It is hereby certified that error appears in the printed specification of :he above numbered patent requiring correction as follows: Page 3, lines 82 and 83,

claim 16, for "a transparent film of an uncolored" read an uncolored transparent film of a; and (hill the said Letters Patent should be read wish this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 7th day of August, A. D. [934.

(Seal) Leslie Frazer Acting Commissioner of Parents.

ules an uncolored transparent solution of a synthetic resin in an organic solvent.

11. The process of treating granular material for surfacing the bituminous coating of roofing, which comprises treating the granules with an uncolored transparent solution of Kauri gum in naphtha.

12. The process of treating granular mineral material, which comprises applying to the granules an uncolorecl transparent oleo-resinous varnish.

13. The process of treating granular mineral material, which comprises applying to the granules an uncolored transparent resinous lacquer.

14. The process of treating granular mineral material, which comprises applying to the granules an uncolored transparent pyroxylin lacquer,

15. A product of manufacture, comprising granular mineral material and a transparent substantially colorless coating thereon of an unvitrifiable material which is insoluble in water and substantially insoluble in bituminous oils.

16. A product of manufacture, comprising granular mineral material and a transparent film of an uncolorecl resin on the surface of the granules.

17. Granular mineral material having thereon an uncolored transparent encasing film of a resinous gum.

18. Composition roofing surfaced with granular mineral material having on the granules an uncolored transparent coating of a resinous gum.

ARTHUR DAWES MACNU'I'I.

CERTIFICATE OF CORRECTION.

Patent No. 1,963, 752.

June l), I934.

ARTHUR DAWES MacNUTT.

It is hereby certified that error appears in the printed specification of :he above numbered patent requiring correction as follows: Page 3, lines 82 and 83,

claim 16, for "a transparent film of an uncolored" read an uncolored transparent film of a; and (hill the said Letters Patent should be read wish this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 7th day of August, A. D. [934.

(Seal) Leslie Frazer Acting Commissioner of Parents. 

